The pygmy short-horned lizard (''Phrynosoma douglasii'') is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of small

horned lizard Horned lizards (''Phrynosoma''), also known as horny toads or horntoads, are a genus of North American lizards and the type genus of the family Phrynosomatidae. The common names refer directly to their horns or to their flattened, rounded bodies, ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Phrynosomatidae The Phrynosomatidae are a diverse family of lizards, sometimes classified as a subfamily (Phrynosomatinae), found from Panama to the extreme south of Canada. Many members of the group are adapted to life in hot, sandy deserts, although the spiny ...

. The species is native to the northwestern

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

and adjacent southwestern

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

. Like other horned lizards, it is often called a "horned toad" or "horny toad," but it is not a

toad Toad is a common name for certain frogs, especially of the family Bufonidae, that are characterized by dry, leathery skin, short legs, and large bumps covering the parotoid glands. A distinction between frogs and toads is not made in scientif ...

at all. It is a

reptile Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...

, not an

amphibia Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arbore ...

n. Sherbrooke, Wade C. (2003). ''Introduction to Horned Lizards of North America.'' California Natural History Guides. Oakland, California: University of California Press. 191 pp. .

Etymology

The specific name, ''douglasii'', is in honor of Scottish

botanist Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek wo ...

David Douglas.

Identification

The pygmy short-horned lizard is often mistaken for its close relative the

greater short-horned lizard The greater short-horned lizard (''Phrynosoma hernandesi''), also commonly known as the mountain short-horned lizard, is a species of lizard endemic to western North America. Like other horned lizards, it is often called a "horned toad" or "hor ...

(''P. hernandesi)'' which has the same basic body type consisting of small pointed scales around the head and back. Until recent

mitochondrial DNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...

evidence, the greater short-horned lizard was considered to be the same species as the pygmy short-horned lizard. They are now considered distinct species with the pygmy short-horned lizard occupying the northwest portion of the United States and extreme southern

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

(now

extirpated Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...

from Canada). When placed together the two are easily distinguished at full size, the pygmy short-horned lizard being much smaller. The greater short-horned lizard is a highly variable species with different geographic populations exhibiting differences in colour, pattern, and size, with some authorities describing five

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

. The pygmy short-horned lizard ranges in size from in snout-to-

vent Vent or vents may refer to: Science and technology Biology *Vent, the cloaca region of an animal *Vent DNA polymerase, a thermostable DNA polymerase Geology *Hydrothermal vent, a fissure in a planet's surface from which geothermally heated water ...

length (SVL) and is a flat-bodied, squat lizard with short spines crowning the head. Stebbins, Robert C. (2003). "''Phrynosoma douglasii'' ", pp. 303–304 + Plate 34 + Map 101. in ''A Field Guide to Western Reptiles and Amphibians: Third Edition''. The Peterson Field Guide Series. Boston and New York: Houghton Mifflin Company. . It has a snub-nosed profile and short legs. The trunk is fringed by one row of pointed scales, while the belly scales are smooth. The colour is gray, yellowish, or reddish-brown, and there are two rows of large dark spots on the back. When threatened or aggressive, its colours become more intense.The pygmy short-horned lizard is also a species at risk in Alberta according to the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).

Behavior and ecology

The diet of ''P. douglasii'' varies from different habitats, but mostly among age and sex classes; neonates feed among almost exclusively on ants (89%) while adults consume fewer ants (72%) and yearlings consume the lowest proportion of ants (60%). It is also considered a lizard that tolerates well low temperatures, so it can reach biomes that are not accessible for most other reptiles.

References

External links

* {{Taxonbar, from=Q898028 Phrynosoma Lizards of North America Reptiles of the United States Fauna of the Western United States Reptiles described in 1828

Etymology

Identification

Behavior and ecology

References

Further reading

External links